Housing with Air Chamber for Battery Monitor System and Method for Manufacturing Same

ABSTRACT

A housing is described that may include a main portion having at least one wall defining an opening that may have a perimeter. The at least one wall may have a rib and an inner wall extending therefrom about the perimeter of the opening. The inner wall may have an air relief slot formed therein. The housing may further include a cover. The cover may have an edge defining a perimeter. The cover may include a rib extending from the edge about the perimeter of the cover. The main portion rib, the inner wall and the cover rib may cooperate for attachment of the cover to the main portion and to define an air chamber between the cover rib and the inner wall.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application Ser.No. 61/861,592 filed Aug. 2, 2013, the disclosure of which is herebyincorporated in its entirety by reference herein.

TECHNICAL FIELD

The following relates to a housing for a battery monitor system (BMS),the housing having an air chamber formed between housing walls and acover for the housing.

BACKGROUND

Battery monitor systems (BMS) include a housing for electrical and/orelectronic components. Laser welding may be used to attach a cover tothe BMS housing. Laser welding is expensive. Due to changes inenvironmental conditions (pressure, temperature, humidity) duringproduct life, it is necessary to have a means to enable air equalizationbetween the product external ambient and the ambient internal to thehousing. Otherwise this might lead to damage in the electroniccomponents inside. This is normally done letting a small gap or slotwithout welding between the housing and the cover.

But such a gap or slot without welding might allow water ingress andfurther protection means have to be added, for example forming anexternal wall in the cover (see, e.g., the prior art housing of FIGS. 10a and 10 b). However this does not adequately prevent water ingress tothe housing due to capillarity that results. As well, to enable thetypical laser used in such laser welding to pass through the cover andreach the housing in order to attach the cover to the housing, the covermust be white in color, thereby requiring a paper label for the housing(instead of direct laser marking on it).

Thus, there exists a need for a housing for a BMS or other systemshaving an air chamber formed between the housing walls and the cover.Such a housing with an air chamber would reduce water ingress to thehousing by minimizing the capillarity effect. Such a housing would alsoenable the use of friction surface welding (FSW) rather than laserwelding to attach the cover to the housing, thereby reducing costs. SuchFSW would also permit the use of a black or dark colored housing,thereby eliminating the need for a paper label as the housing may belabeled by laser marking.

SUMMARY

In at least one embodiment described herein, a housing is provided thatmay include a main portion comprising at least one wall defining anopening having a perimeter. The at least one wall may have a rib and aninner wall extending therefrom about the perimeter of the opening. Theinner wall may have an air relief slot formed therein. The housing mayfurther include a cover. The cover may have an edge defining aperimeter. The cover may further include a rib extending from the edgeabout the perimeter of the cover. The main portion rib, the inner wall,and the cover rib may be configured to cooperate for attachment of thecover to the main portion and to define an air chamber between the coverrib and the inner wall.

In another embodiment described herein, a housing is provided that mayinclude a sidewall extending from a base and defining an opening thatmay have a perimeter. The sidewall may have a rib and an inner wallextending therefrom about the perimeter of the opening. The sidewall maybe adapted to cooperate with a cover to define a housing chamber. Thecover may have an edge defining a perimeter and a rib extending from theedge about the perimeter of the cover. The cover rib and the inner wallmay define an air chamber therebetween. The air chamber may facilitatevibration of the cover relative to the inner wall to attach the cover tothe inner wall by friction welding.

In a further embodiment described herein, a method for manufacturing ahousing is provided. The housing may include a main portion. The mainportion may include at least one wall defining an opening that may havea perimeter. The at least one wall may have a rib and an inner wallextending therefrom about the perimeter of the opening. The housing mayfurther include a cover that may have an edge defining a perimeter. Thecover may include a rib extending from the edge about the perimeter ofthe cover. The method may include abutting the main portion and thecover such that the inner wall of the main portion contacts an innersurface of the cover. The method may further include vibrating the coverrelative to the main portion to at least partially melt the inner walland/or the inner surface of the cover to attach the cover to the mainportion. The cover rib and inner wall may define an air chambertherebetween. The air chamber may facilitate vibration of the coverrelative to the inner wall to attach the cover to the inner wall byfriction welding.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary housing according toembodiments described herein, such as for a battery monitor system,including a housing main portion and cover;

FIGS. 2-4 are perspective views of the exemplary housing of FIG. 1, withthe cover shown as transparent to facilitate illustration of anexemplary friction surface welding process;

FIG. 5 is an enlarged perspective view of a portion of FIG. 4illustrating a friction welded area;

FIG. 6 is an enlarged perspective view of the exemplary housing of FIG.1, with the cover shown as transparent to facilitate illustration of anexemplary friction surface welded area;

FIG. 7 is a perspective view of a cross-section of the exemplary housingof FIG. 6, taken along line 7-7 thereof;

FIGS. 8 a and 8 b are enlarged perspective views of cross-sections ofthe exemplary housing of FIG. 6, taken along lines A-A and B-B thereof,respectively;

FIGS. 9 a and 9 b are cross-sectional views of the exemplary housing ofFIG. 6, taken along lines A-A and B-B thereof, respectively; and

FIGS. 10 a and 10 b are cross-sectional views of a prior art housing andcover for a battery monitor system attached by laser welding.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention.

With reference to the Figures, a more detailed description ofembodiments of a housing 10 for electrical and/or electronic componentsand a method for manufacturing such a housing will be described. Forease of illustration and to facilitate understanding, like referenceshave been used herein for like components and features throughout thedrawings.

According to the embodiments set forth herein, there is generallydescribed a housing for electrical and/or electronic components, such asmay be mounted on a printed circuit board (PCB). The housing maycomprise a main portion having at least one wall defining an opening,the opening having a perimeter. The perimeter of the opening formed bythe at least one wall may comprise a rib, the rib having an inner wallextending therefrom, the inner wall having an air relief slot formedtherein. The housing may further comprise a cover having a rib extendingaround a perimeter of the cover. The main portion rib and inner wall,and the cover rib are each configured to cooperate for attachment of thecover to the main portion of the housing through friction surfacewelding of the cover to the main portion and to form an air chamberbetween the main portion and the cover. A method may also be providedfor manufacturing such a housing.

Referring to FIG. 1, an exemplary housing 20 is shown according toembodiments described herein, such as for a battery monitor system 10,including a housing main portion 22 and a cover 50. As seen therein, thehousing 20 may comprise the main portion 22 and the cover 50. The mainportion 22 may be provided with at least one wall 24 extending from abase 26. The at least one wall 24 may extend around the base 26, forminga sidewall, and define an opening 28. The opening 28 may have aperimeter.

The main portion 22 may be adapted to receive an electrical and/orelectronic component and/or circuit 30 within an interior of the mainportion 22 of the housing 20. The electronic component and/or circuit 30may be mounted on and/or part of a printed circuit board (PCB) 31disposed within the interior of the main portion 22. The electroniccircuit 30 may be adapted for attachment to a battery terminal connector32 received through the at least one wall 24. In that regard, a shunt 33(see also, e.g., FIG. 7) may extend from the terminal connector 32through the at least one wall 24 for connection to the electroniccircuit 30. The shunt 33 may also extend though the at least one wall 24at another location for connection to a chassis cable (not shown). Theat least one wall 24 may also be formed with an opening 34 for anelectrical connector (not shown) configured to connect to the PCB 31 andthe electronic circuit 30.

The at least one wall 24 may have a rib 36 extending from the perimeterof the opening 28. The rib 36 may be configured as a mating surface tocooperate with a cover rib 52. The at least one wall 24 may have aninner wall 38 extending therefrom and about the perimeter of the opening28. The inner wall 38 may have an air relief slot 40 formed therein.

The cover 50 of the housing 20 may have an edge 54 defining a perimeterof the cover 50. The cover 50 may have a rib 52 extending from the edge54 about the perimeter of the cover 50. The rib 52 may be a complete ribaround an external part of the battery monitoring system housing cover50. The cover rib 52 may bound an inner surface 56 of the cover.

FIGS. 2-4 depict the housing 20 of FIG. 1 with the cover 50 shown astransparent to facilitate illustration of an exemplary friction surfacewelding process. FIG. 5 is an enlarged view of a portion of FIG. 4illustrating a friction welded area. The main portion rib 36, the innerwall 38, and the cover rib 52 may cooperate for attachment of the cover50 to the main portion 22 of the housing 20. As shown in FIG. 2, thecover 50 may be placed on the main portion 22 of the housing 20.Abutting the main portion 22 and the cover 50 may align the main portionrib 36 and the cover rib 52 such that the inner wall 38 contacts theinner surface 56 of the cover 50.

As seen in FIG. 3, the engagement of the inner wall 38 with the innersurface 56 of the cover 50 may define a friction welding area 60. Thecover 50 may be welded to the housing by a friction surface welding orvibration welding process. The vibrating of the cover 50 relative to themain portion 22 may heat the area 60. The frictional heating may atleast partially melt the inner wall 38 and/or the inner surface 56 ofthe cover 50 to attach the cover 50 to the main portion 22.

As seen in FIG. 4, after the friction surface welding process, thehousing 20 may be a closed unit. As a closed unit, the cover 50 mayenclose the interior of the main portion 22, defining a housing chamber62. As seen in FIG. 5, the cooperation of the main portion rib 36, theinner wall 38, and the cover rib 52 may define an air gap or air chamber64 between the cover rib 52 and the inner wall 38. The air chamber 64may communicate with the housing chamber 62 via the air relief slot 40.

FIG. 5 illustrates an enlarged view of a portion of the air chamber 64and friction welded area 60 proximate the air relief slot 40. The airchamber 64 may inhibit or reduce water ingress into the housing chamber62. As previously described, the air chamber 64 between the cover 50 andthe inner wall 38 may communicate with housing chamber 62 via the airrelief slot 40. The air chamber 64 may facilitate vibration of the cover50 relative to the inner wall 38 to attach the cover 50 to the innerwall 38. In that regard, the air relief slot 40 may prevent pressure,humidity or temperature differences inside the housing chamber 62 fromthe outside environment that could lead to damage or undesireddeformations in the product electronic circuit 30, such as which mayoccur during expected product working life (for example in a vehicleengine area).

Referring next to FIG. 6, an enlarged perspective view is shown of theexemplary housing 20 of FIG. 1, with the cover 50 shown as transparentto facilitate illustration of an exemplary friction surface welded area60. It should be noted that a suitable coating may be applied to theelectronic circuit 30, including PCB 31, located in the housing chamber62 to protect against humidity.

FIG. 7 illustrates a perspective view of a cross-section of theexemplary housing of FIG. 6, taken along line 7-7 thereof. As seentherein, the air chamber 64 may extend around a perimeter of theinterface between the main portion 22 and the cover 50. The air reliefslot 40 enables communication between interior chamber 62 of the housing20 and the air chamber 64 formed between the cover 50 and the inner wall38 of the main portion 22. The housing chamber 62 may be adapted toreceive the electronic circuit 30 and the PCB 31. The electronic circuit30 may be adapted to cooperate with the battery terminal connector 32 aspreviously described.

Referring next to FIGS. 8 a and 8 b, enlarged perspective views ofcross-sections of the exemplary housing of FIG. 6 are shown, taken alonglines A-A and B-B thereof, respectively. As seen therein, the mainportion rib 36, the inner wall 38, and the cover rib 52 cooperate toform the air chamber 64. As previously described, the air relief slot 40is formed in the inner wall 38.

Still referring to FIGS. 8 a and 8 b, the rib 36 of the main portion 22may define a surface to cooperate with the rib 52 of the cover 50. Theinner wall 38, having an air relief slot 40 formed therein, maycooperate with the inner surface 56 of the cover 50, defining thefriction welded area 60. The air relief slot 40 may be sized toenable/permit some reduction of the air relief slot 40 due to partialmelting of the inner wall 38 that may result from the friction surfacewelding process. In some embodiments an additional air relief slot maybe provided.

FIGS. 9 a and 9 b are cross-sectional views of the exemplary housing ofFIG. 6, taken along lines A-A and B-B thereof, respectively. FIG. 9 aillustrates the air gap or air chamber 64 proximate the air relief slot40. As seen in those Figures, the air gap 64 is formed between the innerwall 38 and the cover rib 52. The air gap 64 is defined by the mating ofthe cover rib 52 with the main portion rib 36 and the engagement of theinner wall 38 with the inner surface 56, and may enable vibration of thecover 50 relative to the main portion 22. The air chamber 64 may bereferred to as an intermediate chamber, and may stop or inhibit wateringress into the interior chamber 62 of the main portion 22 of thehousing 20.

Referring next to FIGS. 10 a and 10 b, cross-sectional views are shownof a prior art housing 20′ and cover 50′, such as for a battery monitorsystem, attached by laser welding. With continuing reference to FIGS. 9a and 9 b, FIGS. 10 a and 10 b illustrate the differences between theprior art attachment of the cover 50′ with the main portion 22′ of thehousing 20′ in comparison to the enhanced sealing and manufacturingfeatures of the embodiments described herein as shown, for example, inFIGS. 9 a and 9 b.

As seen in FIGS. 10 a and 10 b, in the prior art design, the housingdoes not include an air gap or chamber in communication with theinterior 62′ of the main portion 22′ via slot 41. The lack of an air gapmay require welding by laser from the top through the cover 50′ toattach the main portion 22′. To enable or permit laser welding, thecover 50′ must have a color, such as white, that allows the laser topass through the cover 50′. The white color may require labeling with anexternal adhesive paper labeling. The lack of the air gap of the priorart design may enable water ingress by capillarity and a shorter pathfor water intrusion into the interior of the housing 22′.

As previously described, and with reference to FIGS. 9 a and 9 b, theair relieve slot 40 and air gap 64 or intermediate chamber may enablethe cover 50 to be attached to the main portion 22 by friction surfacewelding. The friction surface welding may be performed at a lower costthan attaching the cover 50′ to the housing 20′ by laser welding asshown in FIGS. 10 a and 10 b. The air gap 64 may also greatly inhibit orhighly reduce water ingress into the interior 64 of the housing 20. Asalso previously described, the cover 50 and the main portion 22 may bemade of the same material, which may be a suitable plastic material, andof the same color. The material may be of a darker color to enablelabeling of the cover 50 or the main portion 22 by laser marking.

As is readily apparent from the foregoing, embodiments of a housing 20,such as for use with a battery monitoring system, have been shown anddescribed. The housing 20 may have a cover 50 having an air chamber 64between the housing walls 24 and the cover 50. A method formanufacturing such a housing 20 has also been shown and described. Sucha housing 20 with an air chamber 64 may reduce water ingress to thehousing 20. Such a housing 20 may also reduce costs through the use offriction surface welding rather than laser welding to attach the cover50 to the housing 20, and by permitting the use of a black or darkcolored cover 50, thereby permitting the cover 50 to be labeled by lasermarking and eliminating the need for an adhesive paper label.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the disclosure. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the following claims.Additionally, the features of the various embodiments shown anddescribed herein may be combined to form further embodiments.

1-14. (canceled)
 15. A method for manufacturing a housing including amain portion comprising at least one wall defining an opening having aperimeter, the at least one wall having a rib and an inner wallextending therefrom about the perimeter of the opening, and a coverhaving an edge defining a perimeter, the cover comprising a ribextending from the edge about the perimeter of the cover, the methodcomprising: abutting the main portion and the cover such that the innerwall of the main portion contacts an inner surface of the cover; andvibrating the cover relative to the main portion to at least partiallymelt the inner wall and/or the inner surface of the cover to attach thecover to the main portion; wherein the cover rib and inner wall definean air chamber therebetween, and the air chamber facilitates vibrationof the cover relative to the inner wall to attach the cover to the innerwall by friction welding.
 16. The method of claim 15 wherein the mainportion and the cover comprise the same plastic material.
 17. The methodof claim 15 wherein attachment of the cover to the main portion definesa housing chamber, and the air chamber communicates with the housingchamber via an air relief slot formed in the inner wall.
 18. The methodof claim 17 wherein the air chamber inhibits water ingress to thehousing chamber.
 19. The method of claim 15 wherein the inner wall ofthe main portion is configured to engage an inner surface of the coverto define a friction welding area.
 20. The method of claim 17 whereinthe housing chamber is adapted to receive an electronic component, thecomponent configured for attachment to a battery terminal connector.